1. Field of the Invention
The present invention relates to a continuous sheet processing apparatus for performing a processing such as printing or thermal activation with respect to a continuous sheet, and a method of setting a roll body in the continuous sheet processing apparatus.
2. Description of the Related Art
Hitherto, there is commonly known a continuous sheet processing apparatus, in which a continuous sheet is successively drawn but from a roll body to perform a processing such as printing or thermal activation with respect to the continuous sheet which is drawn out and a portion on which the processing is performed is cut off, thereby obtaining cutform paper.
As a method of holding the roll body in the continuous sheet processing apparatus as described above, as disclosed in Patent Document 1, there is available a method in which a central shaft (roll shaft) is inserted into a central hole of a roll body and end portions of the central shaft, which laterally protrude from the roll body, are supported by a frame (first related art example). Further, as disclosed in Patent Document 2, there is available a method in which a fitting portion of each of bobbins (holders) provided to a frame is inserted into a central hole of a roll body from a side thereof, for supporting the roll body (second related art example). Further, as disclosed in Patent Documents 3 and 4, there is available a method in which a roll body is merely placed on a bottom surface of a roll body accommodating portion (third and fourth related art examples).
[Patent Document 1] JP 2003-146493 A
[Patent Document 2] JP 2000-211777 A
[Patent Document 3] JP 2003-251875 A
[Patent Document 4] JP 2001-293927 A
In the first related art example described above, there are required an operation of inserting the central shaft into the central hole of the roll body and an operation of attaching the central shaft holding the roll body to the frame, thereby being troublesome. Further, in order to prevent a situation where the central shaft detachable with respect to the frame is lost by mistake, thereby making supporting of the roll body thereafter impossible, a user must be cautious. In particular, in a case where the user misconceives that the central shaft is an accessory of the roll body, after processing of an entire continuous sheet drawn out from the roll body is completed, when the roll body is consumed, the central shaft is discarded. After that, when there is a need for a new roll body to be used, the central shaft is not available, so there may arise a problem in that holding of the roll body cannot be performed.
In the second related art example, the bobbin is provided to the frame so as not to be removable therefrom. Accordingly, unlike in the first related art example, there is no risk of losing the bobbin by mistake. Further, by only one operation of inserting the bobbin into the central hole of the roll body, the holding of the roll body is completed. Accordingly, the number of operations decreases compared to the first related art example requiring the two operations. However, the operation of inserting the bobbin into the central hole of the roll body in a confined space of the roll body accommodating portion is extremely complicated. Specifically, positioning of the fitting portion of the bobbin with respect to the central hole of the roll body by fumbling of the user, and moving the fitting portion of the bobbin with respect to the frame to insert the fitting portion into the central hole are extremely complicated. In particular, in a case where a clearance between the fitting portion of the bobbin and the central hole of the roll body is smaller, positioning and insertion operations become more complicated. Further, at a time of positioning or attaching, there is a risk of damaging a side portion of the roll body by a tip of the fitting portion of the bobbin, thereby leaving a flaw or deformation in an edge portion of the continuous sheet.
In the first and second related art examples, when the roll body is not set in a correct position by the central shaft or the bobbin, it is impossible to draw out the continuous sheet from the roll body to supply the continuous sheet to a processing portion.
In contrast, in the third and fourth related art examples, there is no need of an attachment operation of inserting the central shaft or the fitting portion of the bobbin into the central hole of the roll body, or the like, and there is only need of inserting the roll body into the roll body accommodating portion, so operability is remarkably favorable.
An example of the above-mentioned structure is shown in FIG. 19. In this structure, a processing portion 3 is provided above and on a lateral side of a roll body accommodating portion 2 (position shifted in horizontal direction from position directly above central axis of roll body 1a accommodated in roll body accommodating portion 2). A platen roller 5 of the processing portion 3 is rotated, thereby allowing the continuous sheet 1 of the roll body 1a to be successively drawn out to be supplied to the processing portion 3.
The roll body 1a is hardly restricted in a space of the roll body accommodating portion 2 and freely movable therein. Therefore, when the continuous sheet 1 drawn out from the roll body 1a is transported while being pulled by a platen roller 5 provided to the processing portion 3, there is such a risk that the roll body 1a randomly moves in the roll accommodating body 2 by the pulling force. In particular, in the structure as shown in FIG. 19, the processing portion 3 is positioned above the roll body accommodating portion 2. Accordingly, at a time of transporting the continuous sheet 1, there is a fear of the roll body 1a being lifted up. The roll body 1a does not stably become standstill in a state where the roll body 1a is lifted up, and performs irregular operations in the roll body accommodating portion 2. In particular, in a case where the continuous sheet 1 is intermittently transported, when transportation of the continuous sheet 1 is performed (when continuous sheet 1 is pulled up), the roll body 1a is lifted up, and when transportation of the continuous sheet 1 is not performed (when continuous sheet 1 is not pulled), the roll body 1a falls down on a bottom surface of the roll body accommodating portion 2 due to the gravity. In a case where the lifting up and the falling down of the roll body 1a are repeated as described above, large irregular movements of the roll body 1a are caused. As a result, the continuous sheet 1 cannot be correctly supplied to the processing portion 3. Therefore, there occurs operation failures, in which, for example, the continuous sheet 1 is transported while being oriented obliquely, a transport speed becomes nonuniform, and finally, the transportation is impossible. Further, there is a risk of causing abnormalities in processing by a processing head 4 of the processing portion 3, such as printing failure, and variation in or absence of thermal activation.
Further, in the roll body accommodating portion 2, there may be provided a sensor 18 for detecting a size of the roll body 1a, that is, a remaining amount of the sheet by performing detection on a part of the roll body 1a. In this case, when the roll body 1a performs the irregular operations such as the lifting up of the roll body 1a as described above in the roll body accommodating portion 2 and the roll body 1a temporarily gets out of a detection region of the sensor 18, there is a risk of making misjudgment that the remaining amount of the sheet is small regardless of the size of the roll body 1a. 